Integrated modeling and electrochemical study of Myrobalan extract for mild steel corrosion retardation in acidizing media

摘要

In the present study, the corrosion inhibitory impact of Myrobalan aqueous extract was investigated via several experimental (electrochemical and surface) and computer modeling (Monte Carlo (MC), molecular dynamics (MD) and density functional theory (DFT)) studies. Also, the functional groups of Myrobalan extract were characterized by UV-Vis and FT-IR techniques. Results provided by EIS analysis demonstrated 91% efficiency for 1 M HCl aggressive solution protected by 800 ppm Myrobalan extract. The Tafel polarization studies illustrated the suppression of the cathodic/anodic reaction in HCl medium filled with Myrobalan extract. Furthermore, SEM, AFM, and contact angle experiments were carried out for steel surface morphology investigations. The interactions between the inhibitor molecules and metal surface were investigated by different adsorption isotherm models. It is inferred the anti-corrosive molecules interacted with divalent iron cations following a Langmuir isotherm. Moreover, the results of computer modeling studies based on classical simulations and first-principles computations ensured the adsorption of extract molecules on the target metal substrate. (C) 2019 Elsevier B.V. All rights reserved.